fuel pump woes |
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fuel pump woes |
florida 914 |
Dec 8 2013, 09:41 PM
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#1
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Newbie Group: Members Posts: 29 Joined: 29-September 10 From: Salem, OR Member No.: 12,227 Region Association: Pacific Northwest |
I have a 1971 FI 1.7 liter, recently purchased. The car has not run in a long time. I moved the fuel pump to the front under the tank, but am having trouble getting it going. Here is what I know:
The wiring seems to be fine, I mean the part I did, because when I hotwire the pump through the fuel pump relay spot on the relay board (as suggested in the 914 tips book from Autoatlanta) the pump runs. The fuse and relays test fine. But I still get no juice at the pump when the key is on, even for a moment. I also tried to test pin #13 on the board and was unable to confirm that I get juice there, though it is such an awkward test that I am not sure I am doing it right. If that is right then the book suggests that may mean the circuit board is no good -- but then why does the pump run when hotwired through the relay board? Sorry if this is confusing. Any help? |
Mike Bellis |
Dec 8 2013, 09:51 PM
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#2
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Resident Electrician Group: Members Posts: 8,346 Joined: 22-June 09 From: Midlothian TX Member No.: 10,496 Region Association: None |
the FI brain controls when the pump turns on. The trigger points in the distributor trigger the injectors and tell the ECU to turn on the pump.
These early FI systems do not prime when the key is turned on. Does the car crank? Does the pump run while cranking? |
florida 914 |
Dec 8 2013, 10:01 PM
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#3
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Newbie Group: Members Posts: 29 Joined: 29-September 10 From: Salem, OR Member No.: 12,227 Region Association: Pacific Northwest |
the FI brain controls when the pump turns on. The trigger points in the distributor trigger the injectors and tell the ECU to turn on the pump. These early FI systems do not prime when the key is turned on. Does the car crank? Does the pump run while cranking? Ah, that may be the problem. I don't even have spark plugs in yet. I was not trying to start the car, but rather just make sure it was working. I did bump the starter, which did not trigger the pump. |
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